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初始化 ​

主函数 ​

c
	ESP_LOGI(TAG, "Initialize LVGL library");
    lv_init();
    // alloc draw buffers used by LVGL
    // it's recommended to choose the size of the draw buffer(s) to be at least 1/10 screen sized
    lv_color_t *buf1 = heap_caps_malloc(EXAMPLE_LCD_H_RES * 20 * sizeof(lv_color_t), MALLOC_CAP_DMA);
    assert(buf1);
    lv_color_t *buf2 = heap_caps_malloc(EXAMPLE_LCD_H_RES * 20 * sizeof(lv_color_t), MALLOC_CAP_DMA);
    assert(buf2);
    // initialize LVGL draw buffers
    lv_disp_draw_buf_init(&disp_buf, buf1, buf2, EXAMPLE_LCD_H_RES * 20);

    ESP_LOGI(TAG, "Register display driver to LVGL");
	lv_disp_drv_init(&disp_drv);
    disp_drv.hor_res = EXAMPLE_LCD_H_RES;
    disp_drv.ver_res = EXAMPLE_LCD_V_RES;
    disp_drv.flush_cb = example_lvgl_flush_cb;  //实际使用的绘制函数
    disp_drv.drv_update_cb = example_lvgl_port_update_callback;
    disp_drv.draw_buf = &disp_buf;
    disp_drv.user_data = panel_handle;
    lv_disp_t *disp = lv_disp_drv_register(&disp_drv);

    ESP_LOGI(TAG, "Install LVGL tick timer");
    // Tick interface for LVGL (using esp_timer to generate 2ms periodic event)
    const esp_timer_create_args_t lvgl_tick_timer_args = {
        .callback = &example_increase_lvgl_tick,
        .name = "lvgl_tick"
    };
    esp_timer_handle_t lvgl_tick_timer = NULL;
    ESP_ERROR_CHECK(esp_timer_create(&lvgl_tick_timer_args, &lvgl_tick_timer));
    ESP_ERROR_CHECK(esp_timer_start_periodic(lvgl_tick_timer, EXAMPLE_LVGL_TICK_PERIOD_MS * 1000));

#if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
    static lv_indev_drv_t indev_drv;    // Input device driver (Touch)
    lv_indev_drv_init(&indev_drv);
    indev_drv.type = LV_INDEV_TYPE_POINTER;
    indev_drv.disp = disp;
    indev_drv.read_cb = example_lvgl_touch_cb; //使用这一个函数获取实际的触摸的位置
    indev_drv.user_data = tp;

    lv_indev_drv_register(&indev_drv);
#endif

main函数的初始化

输入设备 ​

c
static void example_lvgl_touch_cb(lv_indev_drv_t * drv, lv_indev_data_t * data)
{
    uint16_t touchpad_x[1] = {0};
    uint16_t touchpad_y[1] = {0};
    uint8_t touchpad_cnt = 0;

    /* Read touch controller data */
    esp_lcd_touch_read_data(drv->user_data);

    /* Get coordinates */
    bool touchpad_pressed = esp_lcd_touch_get_coordinates(drv->user_data, touchpad_x, touchpad_y, NULL, &touchpad_cnt, 1);

    if (touchpad_pressed && touchpad_cnt > 0) {
        data->point.x = touchpad_x[0];
        data->point.y = touchpad_y[0];
        data->state = LV_INDEV_STATE_PRESSED;
    } else {
        data->state = LV_INDEV_STATE_RELEASED;
    }
}

获取数模位置的函数

c
static void example_lvgl_flush_cb(lv_disp_drv_t *drv, const lv_area_t *area, lv_color_t *color_map)
{
    esp_lcd_panel_handle_t panel_handle = (esp_lcd_panel_handle_t) drv->user_data;
    int offsetx1 = area->x1;
    int offsetx2 = area->x2;
    int offsety1 = area->y1;
    int offsety2 = area->y2;
    // copy a buffer's content to a specific area of the display
    esp_lcd_panel_draw_bitmap(panel_handle, offsetx1, offsety1, offsetx2 + 1, offsety2 + 1, color_map);
}

实际的绘制函数

c
/* Rotate display and touch, when rotated screen in LVGL. Called when driver parameters are updated.  这一个函数适用于屏幕的旋转的*/
static void example_lvgl_port_update_callback(lv_disp_drv_t *drv)
{
    esp_lcd_panel_handle_t panel_handle = (esp_lcd_panel_handle_t) drv->user_data;

    switch (drv->rotated) {
    case LV_DISP_ROT_NONE:
        // Rotate LCD display
        esp_lcd_panel_swap_xy(panel_handle, false);
        esp_lcd_panel_mirror(panel_handle, true, false);
#if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
        // Rotate LCD touch
        esp_lcd_touch_set_mirror_y(tp, false);
        esp_lcd_touch_set_mirror_x(tp, false);
#endif
        break;
    case LV_DISP_ROT_90:
        // Rotate LCD display
        esp_lcd_panel_swap_xy(panel_handle, true);
        esp_lcd_panel_mirror(panel_handle, true, true);
#if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
        // Rotate LCD touch
        esp_lcd_touch_set_mirror_y(tp, false);
        esp_lcd_touch_set_mirror_x(tp, false);
#endif
        break;
    case LV_DISP_ROT_180:
        // Rotate LCD display
        esp_lcd_panel_swap_xy(panel_handle, false);
        esp_lcd_panel_mirror(panel_handle, false, true);
#if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
        // Rotate LCD touch
        esp_lcd_touch_set_mirror_y(tp, false);
        esp_lcd_touch_set_mirror_x(tp, false);
#endif
        break;
    case LV_DISP_ROT_270:
        // Rotate LCD display
        esp_lcd_panel_swap_xy(panel_handle, true);
        esp_lcd_panel_mirror(panel_handle, false, false);
#if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
        // Rotate LCD touch
        esp_lcd_touch_set_mirror_y(tp, false);
        esp_lcd_touch_set_mirror_x(tp, false);
#endif
        break;
    }
}

输入设备 ​

按键 ​

c
    /*------------------
     * Button
     * -----------------*/

    /*Initialize your button if you have*/
    button_init();

    /*Register a button input device*/
    lv_indev_drv_init(&indev_drv);
    indev_drv.type = LV_INDEV_TYPE_BUTTON;
    indev_drv.read_cb = button_read;
    indev_button = lv_indev_drv_register(&indev_drv);

    /*Assign buttons to points on the screen*/
    static const lv_point_t btn_points[2] = {
            {10, 10},   /*Button 0 -> x:10; y:10*/
            {40, 100},  /*Button 1 -> x:40; y:100*/
    };
    lv_indev_set_button_points(indev_button, btn_points);

这一个是官方的按键的设置

c
/*Will be called by the library to read the button*/
static void button_read(lv_indev_drv_t * indev_drv, lv_indev_data_t * data)
{

    static uint8_t last_btn = 0;

    /*Get the pressed button's ID*/
    int8_t btn_act = button_get_pressed_id();

    if(btn_act >= 0) {
        data->state = LV_INDEV_STATE_PR;
        last_btn = btn_act;
    } else {
        data->state = LV_INDEV_STATE_REL;
    }

    /*Save the last pressed button's ID*/
    data->btn_id = last_btn;
}
/*Get ID  (0, 1, 2 ..) of the pressed button*/
static int8_t button_get_pressed_id(void)
{
    uint8_t i;

    /*Check to buttons see which is being pressed (assume there are 2 buttons)*/
    for(i = 0; i < 2; i++) {
        /*Return the pressed button's ID*/
        if(button_is_pressed(i)) {
            return i;
        }
    }

    /*No button pressed*/
    return -1;
}

/*Test if `id` button is pressed or not*/
static bool button_is_pressed(uint8_t id)
{

    /*Your code comes here*/

    return false;
}
  • 在ESP-IDF里面添加一个按键
c
//按键
gpio_config_t key_gpio_config = {
    .mode = GPIO_MODE_INPUT,
    .pin_bit_mask = 1ULL << GPIO_NUM_23,
    .pull_up_en = 1,
    .pull_down_en = 0,
    .intr_type = GPIO_INTR_DISABLE,

};
ESP_ERROR_CHECK(gpio_config(&key_gpio_config));
c
//按键初始化
lv_indev_t * indev_button;
static lv_indev_drv_t indev_drv;    // Input device driver (Touch)
/*Register a button input device*/
lv_indev_drv_init(&indev_drv);
indev_drv.type = LV_INDEV_TYPE_BUTTON;
indev_drv.read_cb = button_read;
indev_button = lv_indev_drv_register(&indev_drv);

/*Assign buttons to points on the screen*/
static const lv_point_t btn_points[2] = {
    {64, 80},   /*Button 0 -> x:10; y:10*/
};
lv_indev_set_button_points(indev_button, btn_points);
c
/*Will be called by the library to read the button*/
static void button_read(lv_indev_drv_t * indev_drv, lv_indev_data_t * data)
{
    if(gpio_get_level(GPIO_NUM_23) == 0) {
        ESP_LOGI(TAG, "KEY_PRESS");
        data->state = LV_INDEV_STATE_PR;
    } else {
        data->state = LV_INDEV_STATE_REL;
    }

    /*Save the last pressed button's ID*/
    data->btn_id = 0;
}

触摸屏 ​

c
/*------------------
     * Touchpad
     * -----------------*/

/*Initialize your touchpad if you have*/
touchpad_init();

/*Register a touchpad input device*/
lv_indev_drv_init(&indev_drv);
indev_drv.type = LV_INDEV_TYPE_POINTER;
indev_drv.read_cb = touchpad_read;
indev_touchpad = lv_indev_drv_register(&indev_drv);
c
/*Will be called by the library to read the touchpad*/
static void touchpad_read(lv_indev_drv_t * indev_drv, lv_indev_data_t * data)
{
    static lv_coord_t last_x = 0;
    static lv_coord_t last_y = 0;

    /*Save the pressed coordinates and the state*/
    if(touchpad_is_pressed()) {
        touchpad_get_xy(&last_x, &last_y);
        data->state = LV_INDEV_STATE_PR;
    } else {
        data->state = LV_INDEV_STATE_REL;
    }

    /*Set the last pressed coordinates*/
    data->point.x = last_x;
    data->point.y = last_y;
}

时基 ​

c
// Tick interface for LVGL (using esp_timer to generate 2ms periodic event)
const esp_timer_create_args_t lvgl_tick_timer_args = {
    .callback = &example_increase_lvgl_tick,
    .name = "lvgl_tick"
};
esp_timer_handle_t lvgl_tick_timer = NULL;
ESP_ERROR_CHECK(esp_timer_create(&lvgl_tick_timer_args, &lvgl_tick_timer));
ESP_ERROR_CHECK(esp_timer_start_periodic(lvgl_tick_timer, EXAMPLE_LVGL_TICK_PERIOD_MS * 1000));
c
//在这一个函数里面调用lvgl的时基增加的函数
static void example_increase_lvgl_tick(void *arg)
{
    /* Tell LVGL how many milliseconds has elapsed */
    lv_tick_inc(EXAMPLE_LVGL_TICK_PERIOD_MS);
}
c
/*Use a custom tick source that tells the elapsed time in milliseconds.
 *It removes the need to manually update the tick with `lv_tick_inc()`)*/
#define LV_TICK_CUSTOM 0
#if LV_TICK_CUSTOM
    #define LV_TICK_CUSTOM_INCLUDE "Arduino.h"         /*Header for the system time function*/
    #define LV_TICK_CUSTOM_SYS_TIME_EXPR (millis())    /*Expression evaluating to current system time in ms*/
#endif   /*LV_TICK_CUSTOM*/

在lv_config.h这一个文件里面可以设置使用外部的时基